Your requirements could not be resolved to an installable set of packages. Problem 1 - sebastian/diff[4.0.0, ..., 4.0.1] require php ^7.3 -> your php version (8.2.5) does not satisfy that requirement. - friendsofphp/php-cs-fixer[v3.40.0, ..., v3.49.0] require sebastian/diff ^4.0 || ^5.0 -> satisfiable by sebastian/diff[4.0.0, ..., 4.0.5, 5.0.0, ..., 5.1.0]. - You can only install one version of a package, so only one of these can be installed: sebastian/diff[4.0.0, ..., 4.0.5, 5.0.0, ..., 5.1.0, 6.0.0]. - phpunit/phpunit 11.0.0 requires sebastian/diff ^6.0 -> satisfiable by sebastian/diff[6.0.0]. - Root composer.json requires phpunit/phpunit ^11.0.0 -> satisfiable by phpunit/phpunit[11.0.0]. - Root composer.json requires friendsofphp/php-cs-fixer ^3.40.0 -> satisfiable by friendsofphp/php-cs-fixer[v3.40.0, ..., v3.49.0].